Cotillion Records was a subsidiary of Atlantic Records and was active from 1968 through 1985. The label was originally formed as an outlet for blues and deep Southern soul, but its catalogue quickly expanded to include progressive rock, folk-rock, gospel, jazz and comedy. In 1976, the label started focusing on disco and rhythm & blues.
We are not sure how the Walter Bishop Jr. album fits in here; it's a mid-1960s release on a New York-based Cotillion label, so it might be a predecessor of Atlantic's Cotillion or a completely unrelated label with the same name.